Entomobrya boreensis, Jordana & Greenslade, 2020

Jordana, Rafael & Greenslade, Penelope, 2020, Biogeographical and ecological insights from Australasian faunas: the megadiverse collembolan genus, Entomobrya (Entomobryidae), Zootaxa 4770 (1), pp. 1-104 : 24-26

Entomobrya boreensis sp. nov.

( Figs 1E , 4C , 10 A–F)

Holotype. Female, SA, 90 Mile Desert, Ngarkat Conservation Park, Comet Bore, mallee clay pan, - 35.44°S, 140.48.2°E, 25m asl, pitfall, 5−10.x.1977, PG leg., [ SAMA 22667 ].

Paratypes. Two females, same collection data as holotype.

Other material examined. SAMA, 2 male and 2 female , NSW, Broken Hill , in Mitchell grass, 21.ix.1990 ; 60 km ENE Broken Hill, Glen Idol Station , 10.x.1990, - 31.8175°S, 141.933056°E, 165m asl, pitfall .

Description. Size. Length Up to 1.25 mm excluding antennae, (n=8 from 0.98–1.67 mm).

Colour. Uniform pale orange. Head with an anterior stripe purple. Ant 3 and 4 entirely pigmented. Th II to Abd III with the posterior transversal narrow band and laterals one ( Figs 1E , 4C ). Some scattered pigment can be seen under a microscope.

Head. Eight eyes, G and H smaller than E and F. Antennae length 630 μm (n=7), 2.4 times the length of the head (n=7). Ant IV with bilobed apical vesicle with pin chaeta beside it; relative length of Ant I/II/III/IV=1/1.9/2/2.6 (n=7). Sensory organ of Ant III with curved rod-like sensilla in addition to the 3 guard sensilla ( Fig. 10B ); four labral papillae with one short and conical projection each ( Fig. 10A ). Labral formula: 4/554, 4 prelabral ciliated chaetae, labral chaetae smooth. Labial chaetae MEL 1 L 2 all ciliated, only with one Mc M, and without R. External process of labial papilla E reaching the papilla tip.

Thorax and abdomen. Length ratio of Abd IV/III=4 (n=8). Tibiotarsus without differentiated chaetae, with exception of the presence of the smooth terminal chaetae on legs 3, characteristic for the genus. Trochanteral organ from 8 to 12 spiny chaetae. Unguis length 40 μm. Unguis with 4 teeth: paired at 50% of the base and first unpaired at 70-75 % from base; lateral teeth below the level of paired ones. Unguiculus lanceolate, with external serrated lamella. Tenent hair clavate, longer than unguis. The length of manubrium and dens 220 + 353=573 μm (n=8). Manubrial plate with 4 chaetae and 2 pseudopores. Mucro bidentate with anteapical tooth similar in size to apical one, and with mucronal basal spine reaching the tip of the subapical tooth. Mucro 11 μm, (n=8). Length of apical smooth part of dens twice length of mucro.

LP=Labral Papilla: Without =0 smooth =1 Multispinate =2 seta like =3 Pointed not seta like =4. External unguiculus=EU: 0=smooth, 1=serrate. Diff = differences. bor / sti meaning the comparison between the species E. boreensis versus E. stirlingensis . The same abbreviations (first three letters) for the remaining species. * means differences.

Macrochaetotaxy. Simplified Mc formula: 3,1,0,1(2),2/1(2),4/0,2/0,0,1/0,0,3,2,2. Head chaetotaxy ( Fig. 10C ) An 1, An 2, An 3a1 and An 3 Mc. A 5 Mc. M 1 to M 4 present as Mc. In sutural row S 0, S 1 (sometimes absent), S 3, S 4, S 5i and S 5. Ps 2 and Ps 5 present. Thorax chaetotaxy: Th II chaetotaxy ( Fig. 10D ) with Mc m 2 and m 2i2 (sometimes absent) on T1 area. On T2 area Mc a 5, m 4, m 4i and m 5 present (sometimes a 5’ as mesochaeta is present). Abdominal chaetotaxy, a 2 and a 3 absent on A1 area at Abd II, only m 3 and m 3e Mc are present on A2 area of Abd II ( Fig. 10E ). On Abd III only m 3 Mc is present on A5 area, Abd IV ( Fig.10F ) with Mc A 4 –A 6, B 4 –B 6 and C 2a. Sensillary formula 2,2/1,2,2,7,3, mS= 1,0/1,0,1.

Remarks. The new species has the same chaetotaxy on Abd II and Abd III (0,2/0,0,1 Mc) as E. stirlingensis sp. nov. and E. clarki , but differs in the presence of Ps 2 on the head and of 3 Mc on area 8 of Abd IV. The colour differs between these species, and E. boreensis sp. nov. has labral papillae with one short conical projection instead of having a multispinate form as in E. clarki . Other differences are in the absence of labial R chaeta in the new species and the unguis with paired teeth at 32% from base in E. clarki and 50% in E. boreensis . The size also differs, as adults are smaller in E. boreensis than in E. clarki . See Table 5

The distribution of this species is unusual for the genus being found in widespread localities in the arid zone.

Etymology. The species name refers to the type locality.

Figures

FIGURE 1. Habitus and colour of: A, Entomobrya additae sp. nov.; B, Entomobrya albocincta; C, E. assuta; D, Entomobrya bioblitzi, sp. nov.; E. Entomobrya boreensis, sp. nov.; F, Entomobrya caputovisensis sp. nov.; G–H, Entomobrya charlotteensis sp. nov. 7, male, H, female; I, E. clarki; J–K, Entomobrya darelis sp. nov.; L, Entomobrya driesseni sp. nov.; M, Entomobrya durrasensis sp. nov.; N, Entomobrya grisacea sp. nov.; O, Entomobrya herbacea sp. nov. Bar=0.5 mm.

FIGURE 4. Photographs of: A, Entomobrya additae sp. nov., A1, Holotype, A2, dorsal view; B, E. albocincta; C, Entomobrya boreensis sp. nov., Photo: Holotype; D, Entomobrya caputovisensis sp. nov.; E, E. clarki, Lectotype; F, Entomobrya darelis sp. nov., Holotype; G, Entomobrya driesseni sp. nov., Holotype; H, Entomobrya durrasensis sp. nov., Holotype.; I, Entomobrya grisacea sp. nov., Holotype; J, Entomobrya herberti sp. nov., Holotype; K, 25, Entomobrya imbre sp. nov., Holotype; L, Entomobrya karta sp. nov., Holotype; M–N, M, E. lamingtonensis, Holotype and N, specimen from Perth. Bar=0.5 mm.

FIGURE 10. Entomobrya boreensis sp. nov. Line drawings A–F: A, labral papillae bar=0.02 mm; B, Ant III organ bar=0.02 mm; C, head chaetotaxy bar=0.4 mm; D, Th II chaetotaxy; E, Abd II–III chaetotaxy; F, Abd IV chaetotaxy. Bar C, F=0.125 mm. Open circles mean unstable Mc.

Tables

TABLE 5. Comparative characters of E. boreensis sp. nov. and morphologically similar species

	Head				LP	Th II
species/ characters	An3a1	S4i	Ps2	Ps3		m1	m2	m2i	m2i2	m4	m4i	m4p	m5
E. assuta	1	0	1	1	2	0	0	0	0	0	0	0	0
E. bioblitzi sp. nov.	1	0	0	0	2	1	1	0	0	1	1	0	0
E. clarki	0	0	0	0	2	1	0	0	0	1	1	0	1
E. durrasensis sp. nov.	0	0	1	0	4	1	1	1	1	1	1	1	1
E. stirlingensis sp. nov.	0	1	0	0	4	1	1	0(1)	0	1	1	0	1
E. boreensis sp. nov.	0	0	1	0	3	0	1	0(1)	0	1	1	0	1
bor/ass	*			*	*		*			*	*		*
bor/bio	*		*		*	*							*
bor/cla			*		*	*	*
bor/dur					*	*			*			*
bor/sti		*	*		*	*